Stereoselective Synthesis of Nicotinamide β-Riboside and Nucleoside Analogues (original) (raw)

Stereoselective Synthesis of Nicotinamide β-Riboside and Nucleoside Analogues. -The key elements of the stereoselective synthesis of nicotinamide and nicotinic acid β-ribosides (V) involve the formation of silylated nicotinic bases and their coupling with protected sugars (II) under Vorbruggen's conditions in the presence of a catalytic amount of Tms-O-Tf. This method, carried out under controlled conditions, provide only the β-anomers (IV). Basic hydrolytic deblocking of (IV) at low temperature minimizes cleavage of the glycosidic linkage to afford the desired targets (V) as white solids after purification. -(FRANCHETTI*, P.; PASQUALINI, M.; PETRELLI, R.; RICCIUTELLI, M.; VITA, P.; CAPPELLACCI, L.; Bioorg. Med.